feature-removal-schedule.txt 13 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336
  1. The following is a list of files and features that are going to be
  2. removed in the kernel source tree. Every entry should contain what
  3. exactly is going away, why it is happening, and who is going to be doing
  4. the work. When the feature is removed from the kernel, it should also
  5. be removed from this file.
  6. ---------------------------
  7. What: MXSER
  8. When: December 2007
  9. Why: Old mxser driver is obsoleted by the mxser_new. Give it some time yet
  10. and remove it.
  11. Who: Jiri Slaby <jirislaby@gmail.com>
  12. ---------------------------
  13. What: V4L2 VIDIOC_G_MPEGCOMP and VIDIOC_S_MPEGCOMP
  14. When: October 2007
  15. Why: Broken attempt to set MPEG compression parameters. These ioctls are
  16. not able to implement the wide variety of parameters that can be set
  17. by hardware MPEG encoders. A new MPEG control mechanism was created
  18. in kernel 2.6.18 that replaces these ioctls. See the V4L2 specification
  19. (section 1.9: Extended controls) for more information on this topic.
  20. Who: Hans Verkuil <hverkuil@xs4all.nl> and
  21. Mauro Carvalho Chehab <mchehab@infradead.org>
  22. ---------------------------
  23. What: /sys/devices/.../power/state
  24. dev->power.power_state
  25. dpm_runtime_{suspend,resume)()
  26. When: July 2007
  27. Why: Broken design for runtime control over driver power states, confusing
  28. driver-internal runtime power management with: mechanisms to support
  29. system-wide sleep state transitions; event codes that distinguish
  30. different phases of swsusp "sleep" transitions; and userspace policy
  31. inputs. This framework was never widely used, and most attempts to
  32. use it were broken. Drivers should instead be exposing domain-specific
  33. interfaces either to kernel or to userspace.
  34. Who: Pavel Machek <pavel@suse.cz>
  35. ---------------------------
  36. What: RAW driver (CONFIG_RAW_DRIVER)
  37. When: December 2005
  38. Why: declared obsolete since kernel 2.6.3
  39. O_DIRECT can be used instead
  40. Who: Adrian Bunk <bunk@stusta.de>
  41. ---------------------------
  42. What: raw1394: requests of type RAW1394_REQ_ISO_SEND, RAW1394_REQ_ISO_LISTEN
  43. When: June 2007
  44. Why: Deprecated in favour of the more efficient and robust rawiso interface.
  45. Affected are applications which use the deprecated part of libraw1394
  46. (raw1394_iso_write, raw1394_start_iso_write, raw1394_start_iso_rcv,
  47. raw1394_stop_iso_rcv) or bypass libraw1394.
  48. Who: Dan Dennedy <dan@dennedy.org>, Stefan Richter <stefanr@s5r6.in-berlin.de>
  49. ---------------------------
  50. What: old NCR53C9x driver
  51. When: October 2007
  52. Why: Replaced by the much better esp_scsi driver. Actual low-level
  53. driver can be ported over almost trivially.
  54. Who: David Miller <davem@davemloft.net>
  55. Christoph Hellwig <hch@lst.de>
  56. ---------------------------
  57. What: Video4Linux API 1 ioctls and video_decoder.h from Video devices.
  58. When: December 2006
  59. Files: include/linux/video_decoder.h
  60. Why: V4L1 AP1 was replaced by V4L2 API. during migration from 2.4 to 2.6
  61. series. The old API have lots of drawbacks and don't provide enough
  62. means to work with all video and audio standards. The newer API is
  63. already available on the main drivers and should be used instead.
  64. Newer drivers should use v4l_compat_translate_ioctl function to handle
  65. old calls, replacing to newer ones.
  66. Decoder iocts are using internally to allow video drivers to
  67. communicate with video decoders. This should also be improved to allow
  68. V4L2 calls being translated into compatible internal ioctls.
  69. Who: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
  70. ---------------------------
  71. What: PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl])
  72. When: November 2005
  73. Files: drivers/pcmcia/: pcmcia_ioctl.c
  74. Why: With the 16-bit PCMCIA subsystem now behaving (almost) like a
  75. normal hotpluggable bus, and with it using the default kernel
  76. infrastructure (hotplug, driver core, sysfs) keeping the PCMCIA
  77. control ioctl needed by cardmgr and cardctl from pcmcia-cs is
  78. unnecessary, and makes further cleanups and integration of the
  79. PCMCIA subsystem into the Linux kernel device driver model more
  80. difficult. The features provided by cardmgr and cardctl are either
  81. handled by the kernel itself now or are available in the new
  82. pcmciautils package available at
  83. http://kernel.org/pub/linux/utils/kernel/pcmcia/
  84. Who: Dominik Brodowski <linux@brodo.de>
  85. ---------------------------
  86. What: remove EXPORT_SYMBOL(kernel_thread)
  87. When: August 2006
  88. Files: arch/*/kernel/*_ksyms.c
  89. Why: kernel_thread is a low-level implementation detail. Drivers should
  90. use the <linux/kthread.h> API instead which shields them from
  91. implementation details and provides a higherlevel interface that
  92. prevents bugs and code duplication
  93. Who: Christoph Hellwig <hch@lst.de>
  94. ---------------------------
  95. What: CONFIG_FORCED_INLINING
  96. When: June 2006
  97. Why: Config option is there to see if gcc is good enough. (in january
  98. 2006). If it is, the behavior should just be the default. If it's not,
  99. the option should just go away entirely.
  100. Who: Arjan van de Ven
  101. ---------------------------
  102. What: eepro100 network driver
  103. When: January 2007
  104. Why: replaced by the e100 driver
  105. Who: Adrian Bunk <bunk@stusta.de>
  106. ---------------------------
  107. What: drivers depending on OSS_OBSOLETE_DRIVER
  108. When: options in 2.6.20, code in 2.6.22
  109. Why: OSS drivers with ALSA replacements
  110. Who: Adrian Bunk <bunk@stusta.de>
  111. ---------------------------
  112. What: Unused EXPORT_SYMBOL/EXPORT_SYMBOL_GPL exports
  113. (temporary transition config option provided until then)
  114. The transition config option will also be removed at the same time.
  115. When: before 2.6.19
  116. Why: Unused symbols are both increasing the size of the kernel binary
  117. and are often a sign of "wrong API"
  118. Who: Arjan van de Ven <arjan@linux.intel.com>
  119. ---------------------------
  120. What: USB driver API moves to EXPORT_SYMBOL_GPL
  121. When: February 2008
  122. Files: include/linux/usb.h, drivers/usb/core/driver.c
  123. Why: The USB subsystem has changed a lot over time, and it has been
  124. possible to create userspace USB drivers using usbfs/libusb/gadgetfs
  125. that operate as fast as the USB bus allows. Because of this, the USB
  126. subsystem will not be allowing closed source kernel drivers to
  127. register with it, after this grace period is over. If anyone needs
  128. any help in converting their closed source drivers over to use the
  129. userspace filesystems, please contact the
  130. linux-usb-devel@lists.sourceforge.net mailing list, and the developers
  131. there will be glad to help you out.
  132. Who: Greg Kroah-Hartman <gregkh@suse.de>
  133. ---------------------------
  134. What: Interrupt only SA_* flags
  135. When: September 2007
  136. Why: The interrupt related SA_* flags are replaced by IRQF_* to move them
  137. out of the signal namespace.
  138. Who: Thomas Gleixner <tglx@linutronix.de>
  139. ---------------------------
  140. What: PHYSDEVPATH, PHYSDEVBUS, PHYSDEVDRIVER in the uevent environment
  141. When: October 2008
  142. Why: The stacking of class devices makes these values misleading and
  143. inconsistent.
  144. Class devices should not carry any of these properties, and bus
  145. devices have SUBSYTEM and DRIVER as a replacement.
  146. Who: Kay Sievers <kay.sievers@suse.de>
  147. ---------------------------
  148. What: i2c-isa
  149. When: December 2006
  150. Why: i2c-isa is a non-sense and doesn't fit in the device driver
  151. model. Drivers relying on it are better implemented as platform
  152. drivers.
  153. Who: Jean Delvare <khali@linux-fr.org>
  154. ---------------------------
  155. What: i2c_adapter.list
  156. When: July 2007
  157. Why: Superfluous, this list duplicates the one maintained by the driver
  158. core.
  159. Who: Jean Delvare <khali@linux-fr.org>,
  160. David Brownell <dbrownell@users.sourceforge.net>
  161. ---------------------------
  162. What: drivers depending on OBSOLETE_OSS
  163. When: options in 2.6.22, code in 2.6.24
  164. Why: OSS drivers with ALSA replacements
  165. Who: Adrian Bunk <bunk@stusta.de>
  166. ---------------------------
  167. What: ACPI hooks (X86_SPEEDSTEP_CENTRINO_ACPI) in speedstep-centrino driver
  168. When: December 2006
  169. Why: Speedstep-centrino driver with ACPI hooks and acpi-cpufreq driver are
  170. functionally very much similar. They talk to ACPI in same way. Only
  171. difference between them is the way they do frequency transitions.
  172. One uses MSRs and the other one uses IO ports. Functionaliy of
  173. speedstep_centrino with ACPI hooks is now merged into acpi-cpufreq.
  174. That means one common driver will support all Intel Enhanced Speedstep
  175. capable CPUs. That means less confusion over name of
  176. speedstep-centrino driver (with that driver supposed to be used on
  177. non-centrino platforms). That means less duplication of code and
  178. less maintenance effort and no possibility of these two drivers
  179. going out of sync.
  180. Current users of speedstep_centrino with ACPI hooks are requested to
  181. switch over to acpi-cpufreq driver. speedstep-centrino will continue
  182. to work using older non-ACPI static table based scheme even after this
  183. date.
  184. Who: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
  185. ---------------------------
  186. What: ACPI procfs interface
  187. When: July 2008
  188. Why: ACPI sysfs conversion should be finished by January 2008.
  189. ACPI procfs interface will be removed in July 2008 so that
  190. there is enough time for the user space to catch up.
  191. Who: Zhang Rui <rui.zhang@intel.com>
  192. ---------------------------
  193. What: /proc/acpi/button
  194. When: August 2007
  195. Why: /proc/acpi/button has been replaced by events to the input layer
  196. since 2.6.20.
  197. Who: Len Brown <len.brown@intel.com>
  198. ---------------------------
  199. What: sk98lin network driver
  200. When: July 2007
  201. Why: In kernel tree version of driver is unmaintained. Sk98lin driver
  202. replaced by the skge driver.
  203. Who: Stephen Hemminger <shemminger@osdl.org>
  204. ---------------------------
  205. What: Compaq touchscreen device emulation
  206. When: Oct 2007
  207. Files: drivers/input/tsdev.c
  208. Why: The code says it was obsolete when it was written in 2001.
  209. tslib is a userspace library which does anything tsdev can do and
  210. much more besides in userspace where this code belongs. There is no
  211. longer any need for tsdev and applications should have converted to
  212. use tslib by now.
  213. The name "tsdev" is also extremely confusing and lots of people have
  214. it loaded when they don't need/use it.
  215. Who: Richard Purdie <rpurdie@rpsys.net>
  216. ---------------------------
  217. What: Multipath cached routing support in ipv4
  218. When: in 2.6.23
  219. Why: Code was merged, then submitter immediately disappeared leaving
  220. us with no maintainer and lots of bugs. The code should not have
  221. been merged in the first place, and many aspects of it's
  222. implementation are blocking more critical core networking
  223. development. It's marked EXPERIMENTAL and no distribution
  224. enables it because it cause obscure crashes due to unfixable bugs
  225. (interfaces don't return errors so memory allocation can't be
  226. handled, calling contexts of these interfaces make handling
  227. errors impossible too because they get called after we've
  228. totally commited to creating a route object, for example).
  229. This problem has existed for years and no forward progress
  230. has ever been made, and nobody steps up to try and salvage
  231. this code, so we're going to finally just get rid of it.
  232. Who: David S. Miller <davem@davemloft.net>
  233. ---------------------------
  234. What: read_dev_chars(), read_conf_data{,_lpm}() (s390 common I/O layer)
  235. When: December 2007
  236. Why: These functions are a leftover from 2.4 times. They have several
  237. problems:
  238. - Duplication of checks that are done in the device driver's
  239. interrupt handler
  240. - common I/O layer can't do device specific error recovery
  241. - device driver can't be notified for conditions happening during
  242. execution of the function
  243. Device drivers should issue the read device characteristics and read
  244. configuration data ccws and do the appropriate error handling
  245. themselves.
  246. Who: Cornelia Huck <cornelia.huck@de.ibm.com>
  247. ---------------------------
  248. What: i2c-ixp2000, i2c-ixp4xx and scx200_i2c drivers
  249. When: September 2007
  250. Why: Obsolete. The new i2c-gpio driver replaces all hardware-specific
  251. I2C-over-GPIO drivers.
  252. Who: Jean Delvare <khali@linux-fr.org>
  253. ---------------------------
  254. What: drivers depending on OSS_OBSOLETE
  255. When: options in 2.6.23, code in 2.6.25
  256. Why: obsolete OSS drivers
  257. Who: Adrian Bunk <bunk@stusta.de>
  258. ---------------------------
  259. What: libata spindown skipping and warning
  260. When: Dec 2008
  261. Why: Some halt(8) implementations synchronize caches for and spin
  262. down libata disks because libata didn't use to spin down disk on
  263. system halt (only synchronized caches).
  264. Spin down on system halt is now implemented. sysfs node
  265. /sys/class/scsi_disk/h:c:i:l/manage_start_stop is present if
  266. spin down support is available.
  267. Because issuing spin down command to an already spun down disk
  268. makes some disks spin up just to spin down again, libata tracks
  269. device spindown status to skip the extra spindown command and
  270. warn about it.
  271. This is to give userspace tools the time to get updated and will
  272. be removed after userspace is reasonably updated.
  273. Who: Tejun Heo <htejun@gmail.com>
  274. ---------------------------